Guaranteed Power OutputWarranted Tolerance: ± 5%15 year: 90% of its nominal power rating25 year: 80% of its nominal power ratingImpact ResistanceCan bear the force that is generated by one 227gSteel ball fall down from 1m heightWarranty period10 years: Materials and workmanship defectsCellsMonocrystalline silicon photovoltaic cell